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We describe the luminescence spectral properties of CdS nanoparticles with multiphoton excitation. Three types of CdS nanoparticles were examined which were a CdS/dendrimer composite which displays high anisotropy, Cd2+-enriched nanoparticles which display two emission maxima, and polyphosphate-stabilized nanoparticles which display long wavelength emission. Illumination with long wavelengths near 700−790 nm resulted in two-photon excitation. Essentially the same emission spectra and intensity decays were observed with one-photon and two-photon excitation. Comparison with fluorescein indicates the NPs display large two-photon cross sections near 100 GM. The CdS/dendrimer and Cd2+-enriched CdS nanoparticles displayed large anisotropy values with two-photon excitation, substantially larger than with one-photon excitation. It appears that semiconductor nanoparticles are comparable to organic fluorophores which display the same spectral properties with one-photon and two-photon excitation.
Answer: Hydrogen is diatomic.
Explanation:
Because hydrogen exists as a diatomic molecule.
The answer is not A because in A, two aqueous solutions(solutions which are diluted and aren’t concentrated) are reacting to produce a gas.
Answer:
Lead
Explanation:
As you move down the periodic table, the elements get larger and gain additional electron shells, increasing the radius. In order, they are on the table as Chlorine, Selenium, Lead.
<h3>
Answer:</h3>
pH = 8.66
<h3>
Explanation:</h3>
- The pH refers to the acidity or alkalinity of a solution.
- It is calculated by getting the negative logarithm of Hydrogen ions concentration.
In this case;
we are given [OH⁻] as 4.6 x 10^-6 M
We are required to calculate the pH
We need to know that;
pH + pOH = 14
pOH = -log[OH⁻]
To get the pH we can calculate the pOH first,
pOH = -log[4.6 x 10^-6 M]
= 5.34
but, pH + pOH = 14
Therefore, pH = 14 - pOH
= 14 - 5.34
= 8.66
Therefore, the pH of the solution is 8.66